9981397 has 8 divisors (see below), whose sum is σ = 10679256. Its totient is φ = 9295872.

The previous prime is 9981383. The next prime is 9981463. The reversal of 9981397 is 7931899.

9981397 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 654481 + 9326916 = 809^2 + 3054^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 9981397 - 2¹⁹ = 9457109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9981317) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1378 + ... + 4675.

It is an arithmetic number, because the mean of its divisors is an integer number (1334907).

Almost surely, 2^9981397 is an apocalyptic number.

9981397 is a gapful number since it is divisible by the number (97) formed by its first and last digit.

It is an amenable number.

9981397 is a deficient number, since it is larger than the sum of its proper divisors (697859).

9981397 is a wasteful number, since it uses less digits than its factorization.

9981397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6167.

The product of its digits is 122472, while the sum is 46.

The square root of 9981397 is about 3159.3348983607. The cubic root of 9981397 is about 215.3097895791.

The spelling of 9981397 in words is "nine million, nine hundred eighty-one thousand, three hundred ninety-seven".